The present invention relates to an outrigger assembly for stabilizing a mobile work machine. More specifically, the present invention is an outrigger assembly for stabilizing a self-propelled, vehicle-mounted conveyor system used to place concrete or other materials in a desired location.
Vehicle-mounted, extendable concrete conveyor systems, such as shown in U.S. Pat. No. 4,624,357, have been in use for some time. In such vehicles, a discharge conveyor assembly includes a telescoping boom having its base end pivotally mounted to the torque tube of the vehicle chassis. The substantial amount of weight extending from the vehicle chassis necessitates the use of outriggers to stabilize the vehicle and prevent the vehicle from tilting or overturning.
The most common type of outrigger system includes a plurality of leg members that can each be extended from a stationary housing fixed to the vehicle. An example of this type of outrigger is shown in U.S. Pat. No. 4,949,808. The leg member in this outrigger includes a support pad that contacts the ground to stabilize the vehicle.
A vehicle-mounted conveyor system presents unique problems in the design of the outrigger assembly. Specifically, both the discharge conveyor assembly and the infeed conveyor assembly are rotatable about a turntable assembly mounted to the vehicle chassis. Since both the infeed conveyor assembly and the discharge conveyor assembly can rotate about the vehicle, it is possible that the conveyor assemblies could contact the outrigger assemblies mounted to the vehicle. Therefore, an important design consideration is to provide individual outrigger assemblies that are constructed to prevent both the infeed conveyor assembly and the discharge conveyor assembly from contacting the outrigger assemblies as the conveyors rotate about the vehicle chassis.
Due to the length of the extendable boom contained on the discharge conveyor, a significant amount of weight positioned away from the center of gravity of the vehicle must be supported by the vehicle chassis. Therefore, in addition to being designed to avoid contact with the conveyor assemblies, the outrigger assemblies must extend a sufficient distance from the vehicle chassis in order to provide the required stability for the vehicle.
It is an object of the present invention to provide an outrigger assembly for use with a vehicle-mounted conveyor system to provide the required stability for the vehicle while preventing possible contact between the main discharge conveyor assembly and the individual outriggers. Further, it is an object of the present invention to provide a plurality of outrigger assemblies in which each outrigger assembly is contained within the overall vehicle width when in its completely retracted position. Further, it is an object of the present invention to provide an outrigger assembly that includes a leg assembly having a support pad that seals the open interior of the support housing when the leg member is in its fully retracted position. Additionally, it is an object of the present invention to provide an outrigger assembly that include a two part telescoping assembly to increase the distance the support pads extend from the vehicle chassis while minimizing the storage area of the outrigger assembly.
The present invention is an outrigger assembly for use with a mobile work machine, such as a vehicle-mounted telescopic belt conveyor, to stabilize the machine when the machine is operating. The work machine includes a plurality of the individual outrigger assemblies to provide multiple points of stabilization for the vehicle when the extendable belt conveyor is in use.
Each outrigger assembly includes a generally hollow support housing that is securely mounted to the torque tube of the vehicle. The width of the support housing is approximately equal to the width of the vehicle. The support housing defines an open interior that receives a telescoping inner housing.
The inner housing is telescopically movable into and out of the support housing between a retracted position and an extended position. The movement of the inner housing between its extended position and its retracted position is controlled by a first drive cylinder. The cylinder body of the first drive cylinder is securely attached to the inner housing, while the end of the cylinder rod of the first drive cylinder is securely fixed to the stationary support housing. When the first drive cylinder is actuated, the movement of the cylinder rod out of the cylinder body results in the outward movement of the inner housing from within the open interior defined by the support housing. Likewise, retraction of the cylinder rod into the cylinder body of the first drive cylinder results in movement of the inner housing toward the retracted position in which the inner housing is nearly completely contained within the support housing.
The outrigger assembly further includes a leg assembly that is telescopically contained within the open interior defined by the inner housing. The leg assembly includes a leg member pivotally attached to a mounting beam. The mounting beam, in turn, is movable within the open interior of the inner housing between an extended position and a retracted position. When the mounting beam is in the fully retracted position, a support pad mounted to the leg member covers the opening to the open interior of the inner housing.
The movement of the leg assembly between the retracted position and the extended position is controlled by a second drive cylinder. The cylinder body of the second drive cylinder is coupled to the mounting beam, while the cylinder rod of the second drive cylinder is fixed at its outer end to the inner housing. When the cylinder rod is extended from the cylinder body of the second drive cylinder, the mounting beam, and thus the entire leg assembly, moves from the retracted position to the extended position. In the extended position, the leg member is positioned completely out of the inner housing.
The leg member is pivotally attached to the mounting beam about a pivot rod passing through the inner end of the support leg. A pivot cylinder is positioned between an upper portion of the inner end of the leg member and the mounting beam. Specifically, one end of the pivot cylinder is securely fixed to the mounting beam, while the cylinder rod of the pivot cylinder is attached to an attachment pin passing through the inner end of the support leg. The attachment pin securing the cylinder rod of the pivot cylinder to the leg member is positioned above the pivot rod connecting the leg member to the mounting beam. In this manner, when the pivot cylinder is actuated, the movement of the cylinder rod out of the cylinder body results in downward movement of the leg member from the extended position to a ground-engaging position.
As the leg member moves to the ground-engaging position, the support pad mounted to the outer end of the leg member contacts the ground to stabilize the work machine. Further extension of the cylinder rod of the pivot cylinder results in the lifting of the vehicle body off of the ground to further stabilize the machine during operation. An advantage of the outrigger assembly of the present invention is that it is compact in size when in the retraction position yet extends far enough from the vehicle body to provide the required stabilization for a large telescoping boom conveyor system. Further, the leg member of each outrigger assembly is angled from the extended inner housing to allow the telescoping boom of a mobile conveyor system to be rotated around the vehicle without the possibility of contact with any portion of the outrigger assemblies.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.